Abstract

Amplitude dependence of the Shapiro steps is studied in the ac driven overdamped Frenkel–Kontorova model with deformable substrate potential. It was found that as potential gets deformed, appearance of large subharmonic steps strongly influence the properties of harmonic steps. In their amplitude dependence, different types of behavior have been classified and deviation from the well known Bessel-like oscillations has been observed. These phenomena may significantly influence stability and existence of interference effects in real systems.